Printing system

ABSTRACT

There is disclosed a dot matrix or telegraphic progressive printing system including an encoding device such as keyboard or reader, a code translator, and a printer for progressively printing a symbol on a record medium during each printing cycle. In the illustrated embodiments, a platen having platen edges rotates continuously, a carriage travels at a constant rate relative to the platen during each printing cycle, and a print hammer mounted by the carriage cooperates with successive platen edges or elements of the platen in accordance with the symbol pulse units received from the code translator. The printing cycle for a selected symbol is initiated when a stored signal is ready to be applied to the printer and a platen element is in the proper position relative to the print hammer.

United States Patent [72] Inventors Wilburn F. Bradbury Northbrook;

George E. Misthos, Glenview, both of III. [21] Appl. No. 781,412 [22]Filed Dec. 5, 1968 [45] Patented Dec. 21,1971 [7 3] Assignee SCMCorporation New York, N.Y.

[54] PRINTING SYSTEM 22 Claims, 35 Drawing Figs.

3,291,909 12/1966 Clarketal. 3,324,240 6/1967 Kleinschmidtetal.

ABSTRACT: There is disclosed a dot matrix or telegraphic progressiveprinting system including an encoding device such as keyboard or reader,a code translator, and a printer for progressively printing a symbol ona record medium during each printing cycle. In the illustratedembodiments, a platen having platen edges rotates continuously, acarriage travels at a constant rate relative to the platen during eachprinting cycle, and a print hammer mounted by the carriage cooperateswith successive platen edges or elements of the platen in accordancewith the symbol pulse units received from the code translator. Theprinting cycle for a selected symbol is initiated when a stored signalis ready to be applied to the printer and a platen element is in theproper position relative to the print hammer.

PATENIEHIIEEZI an 3.6291504 SHEET 1 OF 7 WILBURN F. BRADBURY GEORGE. E.M|5TH05 PATENTED Um] Ian 3' 29' 504 sum 2 0r 7 WILBURN F. BRADBURYGEORQE E. MISTHOS dim/4 PATENTED DEL21 :sm 1 3 529,5

SHEET 3 BF 7 WILBURN F. BRADBURY GEORGE E:.MISTH05 PATENTED new I971SHEET 8 OF 7 WILBURN F. BRADBURY GEORGE E. MISTHOS M PRINTING SYSTEMBACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates in general to the art of dot matrix printing systems and inparticular to telegraphic progressive printing systems.

2. Description of the Prior Art A printing system disclosing a priordevelopment in the art to which this invention pertains is found in U.S.Pat. No. 3,324,240.

SUMMARY OF THE INVENTION The invention comprises a system for dot matrixprinting of successive symbols on a record medium. A symbol signalgenerated at a keyboard, a reader, or the like is translated into asignal having pulse units representative of the selected symbol. Aselected signal is stored, for example when a corresponding symbol keyis depressed, and concomitantly a predetermined pattern is set up in amatrix. The printer has a continuously moving platen with platenelements or edges and a print hammer mounted on a carriage which movesrelative to the platen. When a signal has been stored and a platenelement is in proper position, as sensed by a sensing device, to startprogressive printing at one or more locations in a first column on therecord medium, operation of a commutator is initiated. Initiation ofoperation of the commutator is considered to initiate readout of thestored signal and hence to initiate the printing cycle. A sensing devicecontinuously senses the position of the platen elements and drives thecommutator which controls the rate of readout of the stored signal. Theplaten continues to move even though the printing cycle for one symbolis complete. In like manner, when the next signal has been stored andthe platen is in proper position as sensed by the sensing device, theprinting cycle for the next symbol commences.

The invention also comprises improved carriage and carriage-guidingstructure and transducer-mounting structure. Various other objects andfeatures of the invention will be apparent from the drawings and thedescription of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a diagrammatic view of a dotmatrix printing system including a keyboard, a code translator, and aprinter having a platen with platen edges and a cooperating printhammer;

FIG. 2 is a cutaway perspective view of the principal components of thekeyboard and code translator depicted in FIG.

FIG. 3 is a vertical sectional view of a commutator, its drive train,and a start-stop mechanism depicted in FIG. 2;

FIG. 4 represents the commutator segments wired for the letter E;

FIG. 5 is a schematic layout of the forty-eight segments of thecommutator, a portion of an exemplary diode matrix group, and several ofthe key switches; the matrix group portion shown is wired to the propercommutator segments and to selected key switches to result intransmission of the letters M, H, B, E, S, V and X when the respectivekey switch is closed;

FIG. 6 is a perspective view of a tape reader;

FIG. 7 is a side elevational view of a printer for carrying out theinvention;

FIG. 8 is a fragmentary perspective view of the side of the printerdepicted in FIG. 7;

FIG. 9 is a fragmentary side elevational view showing various componentsin different positions from the position shown in FIGS. 7 and 8;

FIG. 10 is a front elevational view of the printer;

FIG. 11 is an enlarged fragmentary elevational view showing the side ofthe printer which is opposite from the side shown in FIG. 7;

FIG. 12 is a fragmentary view as viewed upwardly and rearwardly from thelower front part of the printer;

FIG. 13 is a fragmentary sectional view of a clutch, a drive pulley anda gear shown in elevation in FIG. 10;

FIG. 14 is an enlarged sectional view showing the platen in relation toa carriage which carries a print hammer, the print hammer being shownout of printing cooperation with the platen and the record medium;

FIG. 15 is an elevational view of the carriage, the print hammer, andfragmentary portions of the feed screw and a guiding and actuating shaftor rod, as viewed from the front of the printer;

FIG. 16 is a perspective view of the print hammer;

FIG. 17 is a sectional view through the feed screw and a hearing whichis secured to the carriage, together with a fragmentary portion of thefeed pawl;

FIG. 18 is a view taken along line 18-18 of FIG. 17;

FIG. 19 is a sectional view taken along line 19l9 of FIG. 17;

FIG. 20 is a diagrammatic view showing another embodiment of the systemshown in FIG. 1;

FIG. 21 is a diagram of a grid block arrangement showing shadedlocations or dots printed during progressive printing of the symbol E;

FIG. 22 is a diagrammatic view showing in detail structure depicted bylogic symbols in FIG. 20;

FIG. 23 is a fragmentary view showing the arrangement by which a symbol,such as symbol E, can be stored in the code translator;

FIG. 24 is a diagrammatic view showing how the pulse units of a symbolsignal can be sensed during readout in a predetermined sequence;

FIG. 25 is a front elevational view of a drive motor, position-sensingdevices, and structure of mounting the sensing devices to a shaft whichis driven by the motor;

FIG. 26 is an elevational view of the motor, sensing devices, andmounting structure as viewed from the left side of FIG. 25;

FIG. 27 is a fragmentary top plan view taken along line 27- 27 of FIG.25;

FIG. 28 is a circuit diagram illustrating a variable rate time basegenerator or oscillator illustrated in logic symbol form in FIG. 20;

FIG. 29 is a circuit diagram of a one-shot multivibrator illustrated inlogic symbol form in FIG. 20;

FIG. 30 is a circuit diagram of a print hammer operating circuit andamplifier illustrated in logic symbol form in FIG. 20;

FIG. 31 is a circuit diagram illustrating a transducer circuit shown inlogic symbol form in FIG. 20;

FIG. 32 is a circuit diagram of a one-shot multivibrator shown in logicsymbol form in FIG. 20;

FIG. 33 is a circuit diagram illustrating a sense amplifier shown inlogic symbol form in FIG. 20;

FIG. 34 is a circuit diagram of an integrated circuit l/IO decoder andassociated NAND gates shown in logic symbol form in FIG. 20; and

FIG. 35 is a fragmentary view of a keyboard for storing signals in amemory device depicted in FIG. 20, a control register, a senseamplifier, and an arrangement for effecting carriage return.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the FIG. 1 of thespecific embodiment of FIGS. 1 through 5 and 7 through 19 of thedrawings, there is diagrammatically illustrated a dot matrix printingsystem generally indicated at 35 including a keyboard 36 linked to aprinter 37 by a code translator 39. Details of the keyboard 36 and thecode translator 39 are depicted in FIGS. 2, 3, 4, and 5 and correspondgenerally to keyboard and code translator structure depicted in US. Pat.No. 3,324,240, to which reference may be had for additional details.

The keyboard 36 has symbol selecting means in the form of a set of keys38, only one of which is illustrated. When the selected key 38 isdepressed it will pivot associated levers 41 and 42 counterclockwise(FIG. I) to in turn pivot associated switch operator lever 47 clockwise.Clockwise pivoting of lever 47 will close associated leaf switch 49 andwill thereafter effect closing of a leaf switch 50. Closure of theswitch 49 completes a circuit to a diode matrix or diode matrix bank 51,thereby setting up a predetermined circuit through certain diodes inaccordance with the key 38 which was depressed. It is apparent thatdepression of any key 38 effects storage of its respective symbolsignal. Closure of the switch 50 complete a circuit to the startingmechanism for a commutator 52, provided a switch 50' of the printer 37is closed. Thus, when both switches 50 and 50' are simultaneouslyclosed, a circuit is completed through a one-shot multivibrator 55 to astarting electromagnet 56. Energization of the electromagnet 56 causesattraction of an armature 57, best shown in FIG. 2, pivoting it untilits blocking end 58 moves out of the path of a blocking lever 59. Withthe blocking end 58 removed from its path, blocking lever 59 andcommutator shaft 60 will start rotating due to force transmitted from amotor 64 through gears 63 and 62 and a slip clutch 61.

A wiper disc 66 (FIG. 3) attached to the commutator shaft 60 worked insliding contact relationship with a brush contact 67. A wiper 65 carriedby the disc 66 can make wiping contact with the segments of thecommutator 52. It is through the brush contact 67 that electrical pulseunits are sent over an output line to an amplifier 68. The codetranslator 39 and the amplifier 68 can be located either at thetransmitting station or at the receiving station. The code translator 39is considered to include the matrix 51 and the commutator 52.

The portion of the matrix 51 shown in FIG. 5 of this application differsfrom the one shown in FIG. 23 of US. Pat. No. 3,324,240, in that (inFIG. 5) segments designated 039, 040, and 041 are dead segments becausethey are not part of any circuit, segments 042 and 043 are electricallyconnected to the output of an oscillator 70 which generates a continuoussignal at a particular frequency, for example, 1,500 cycles per second,and segments 036, 037 and 038 are electrically connected to the outputof a gated oscillator 71 which generates signals at a selected frequencywhich is different from, and in particular is higher than, the frequencyof the signals generated by the oscillator 70. For example, theoscillator 71 is one that generates a continuous signal of 2,000 cyclesper second.

So long as the electromagnet 56 remains deenergized, the wiper 65 willremain in contact with the dead segment 040. When the selected key 38 isdepressed it will cause closure of the switch 49 thereby setting up thecircuit paths for the selected symbol, and thereafter when switches 50and 50' are closed to energize the electromagnet 56, the blocking end 58moves out of the path of the blockinglever 59 enabling the shaft 60, thewiper 65, and the disc 66 to make one complete revolution at constantrotational speed. As the platen 127 is in proper position whenelectromagnet 158 is energized, initiation of the printing cycle of theprinter 37 is synchronized with the code translator 39. During thiscomplete revolution, the wiper 65 will successively make wiping contactwith segments 041, 042, 043 and segments 01 through 07, 08 08 through014, I 015 through 021, 022 0 22 through 028, 029 029 through 035, 036and 036 to 040. When the wiper 65 makes contact with the dead segment041 no signal is generated; however, when the wiper 65 makes contactwith abutting segments 042 and 043 the output signal from the oscillator70 will be applied to the amplifier 68. This signal will be detected bya detector 70 which is connected to the amplifier 68. The detector 70detects any signal having a frequency of 1,500 cycles per second orhigher; detection of this signal will effect energization of a clutchcoil 232. Each energization of coil 232 will cause starting of astart-stop device, specifically it will cause engagement of a clutch 203(FIG. to cause a printer carriage 164 to move away from thestart-of-line position. As the wiper 65 successively makes wipingcontact with segments 01 through 035, an electrical symbol signalcomposed of a succession of selectively time-spaced electricalintrasignal pulse units representative of the selected symbol will beapplied to the amplifier 68. For example, for the symbol or letter Esegments 01 through 08, M I, M4, 015, 018, MI, 022, 025, 028, 029 and035 (FIGS. 4 and 5) are connected via circuit paths of the diode matrix51 to positive potential through the switch designated E in FIG. 5:therefore, as the wiper 65 successively makes contact with each of thesesegments an electrical pulse unit, in particular a current pulse unit,will be applied to the amplifier 68. It is apparent that the time-spacedpulses generated as the wiper 65 wipes across the segments 0l through035 will be of the binary type, in this instance either of thecurrenttype or of the no-current type. Current pulses are detected by aprint pulse detector 72 which is connected to the amplifier 68. A printcoil 316 is energized each time a current pulse is detected by the printpulse detector 72. When the wiper 65 completes its contact with thesegment 035, the symbol will be completely printed. As the wiper 65wipes across abutting segments 036, 037 and 038, the signal generated bythe oscillator 71 will not be applied to the amplifier 68 unless thecarriage return key 38 is depressed. It is only when the carriage-returnkey 38 is depressed and the wiper 65 wipes across segments 036, 037 and038 that the oscillator 71 is gated and thus applies a 2,000 cycle persecond output signal to these segments. A detector 71 will detect thesignal generated by the oscillator 71, as amplified by the amplifier 68,to cause energization of a carriage return coil 259. As the frequency ofthe signal which is applied to detector 71 is also applied to thedetector 70, and as that signal is of a higher frequency, namely higherthan 1,500 cycles per second, the detector 70' will also detect thatsignal, thereby also energizing clutch coil 232. Depression of thecarriagereturn key 38 will not set up any current paths in the matrix 51as its associated switch 49 is not connected to the matrix Thetransmitter which is used can include a keyboard as depicted in FIGS. 1and 2, a tape reader R as depicted in FIG. 6, or the like. When using areader instead of a keyboard in the embodiment of FIGS. 1 through 5 and7 through 19 the reader would be of a type having one outputcorresponding to each symbol which is to generate; in particular, eachoutput would be connected to the diode matrix 51.

The printer 37 is shown in detail in FIGS. 7 through 19 of the drawings.Some of the printer components depicted in this application are similarin construction to the printer components disclosed in US. Pat.application Ser. No. 632,955, to which reference may be had foradditional details. The printer 37 is shown to include a continuouslydriven platen 127 having a plurality of equally spaced parallel platenelements or edges 138 about its periphery. The platen elements 138extend the full length of the platen 127. A record medium R (FIG. 14) isdisposed between the platen 127 and a lineshaped print face 142 of aprint hammer 299. The record medium R is preferably composed of treatedpaper so as the print face 142 impacts the paper and presses The paperagainst the cooperating platen edge 138, a permanent contrasting mark isformed thereon. In the event it is desired to use untreated paper, anink-ribbon (not shown) can be fed between the print face 142 of theprint hammer 299 and the untreated paper.

An electric motor 199 (FIG. 1) drives the platen 127 at constant speedthrough toothed pulleys 200 and 202 and a toothed belt 201, and gears307 and 308. Secured to platen drum shaft 302 is a cam 303 which hasequally spaced-apart cam lobes 304 equal in number and corresponding tothe platen elements 138 of the platen 127. As the cam 303 rotates, lobes304 acting on switch arm 305 of the switch 50' cause the contacts of theswitch 50' to open and close. The position of the switch 50' isadjustable with respect to the cam 303 by an adjusting screw 306. Whenthe switch S0 is properly adjusted, printing of a symbol on the recordmedium R will be initiated when the element 138 is in the properposition with respect to the face 142 of the print hammer 299.

Referring to FIGS. 7 through 19, a frame 121 is shown to rotatably mountthe platen drive shaft 302, a feed screw 193, a

shaft 163, and a guiding and actuating member or shaft 165 which isparallel to the feed screw 193. The feed screw 193 is driven wheneverthe clutch 203 is engaged. When the electromagnet 229 (FIG. 11) isenergized, the latch element 228 is tripped to enable arm 240 to pivotcounterclockwise out of abutment with tooth 241. Thereupon, wrappedspring 213 (FIG. 13) engages clutch surface 217. Engagement of theclutch 203 causes the feed screw 193 to make one complete revolution,thereby driving carriage 164 a distance equal to one symbol space plus asmall additional distance to provide a space between each symbol and thenext successive symbol. The carriage 164 is mounted for travellengthwise with respect to the platen 127.

Carriage return is accomplished by energizing electromagnets 229 and158, thereby engaging the clutch 203 to cause rotation of the feed screw193 and tripping latch member 255 to enable lever 250 to pivot clockwise(FIG. 9). The lever 250 has a pin 272 against which a latch member 270is urged by a spring 273. The latch member 270 has a hub 271 which issecured to the shaft 165. As the lever 250 pivots clockwise (FIG. 9),the pin 272 drives member 270 and shaft 165 clockwise. When the shaft165 pivots clockwise (FIGS. 9 and 14), a spring 196 pivots a couplingmember in the form of a feed pawl generally indicated at 190 out ofcoupling engagement with the feed screw 193 and a bearing 308 which issecured to the carriage 164. A carriage return spring 277 (FIG.connected at one end to a bracket 277' secured to the carriage 164 istrained about a pulley 309 and is connected at its other end to theframe 121. When the lever 250 is pivoted clockwise (FIG. 9), a rollerfollower 261 carried by the lever 250 moves into the path of the cam207. As the cam 207 is rotated one revolution, feed pawl 262 drivesratchet wheel 263 which in turn drives the shaft 163. Gears 162 and 162secured to the shaft 163 mesh with and drive gears 160 and 161, therebydriving feed wheels 146 and 147 which cooperate with rollers 154 and 155to feed the record medium R. When adjustable screw-type actuator 281mounted by the carriage 164 strikes a latch member 274 (FIG. 8), a latch270' formed by latch members 270 and 274 is tripped to enable latchmember 270 to pivot counterclockwise FIG. 9) under the force of thespring 273. A resilient stop or bumper 282' (FIG. 15) secured to acarriage frame 309 strikes the side panel of the frame 121 and definesthe start-of-line position of the carriage 164.

The carriage frame 309 has mounting portions 310 and 311 arranged toprovide a U-shaped opening 312. A set screw 184' is threadably receivedand mounted by the mounting portion 310. The force which spring 184exerts on the print hammer 299 can be regulated by adjusting the setscrew 184'. An electromagnet generally indicated at 313 is shown toinclude a U- shaped core 314 having a leg 315 about which a print coil316 is received and another leg 317 which is clamped between arms 318and 319 of the mounting portion 311. Screws 320 pass through bores inthe arm 318 and through enlarged bores in the Ieg317 of the core 314.The screws 320 are threadably received by the arm 319. Hence, theelectromagnet 313 is able to be adjusted with respect to armature 321 ofthe print hammer 299.

A hub 332 is provided at one end of the armature 321 of the print hammer299. A pivot pin 333, secured in the arms 318 and 319, is received inbore 332 of the hub 332. A relatively thin print hammer section 334 isformed integrally with the other end of the armature 321. The armature321, which is relatively thin, extends in one plane and the print hammersection 334 extends in a plane which is perpendicular to the plane ofthe armature 321. The print hammer section 334 joins the armature 321 atan obtuse angle as best seen in FIGS. 14 and 16. The print hammersection 334 has a keeper 335 which receives the marginal end of thespring 184. One end of the spring 184 abuts the print hammer section 334at lands 336 at each side of the keeper 335. As best shown in FIG. 14,the spring 184 exerts a force on the print hammer 299 at right angles,as is evident from the fact that the center line of the bore 332' andthe lands 336 lie along one straight line and the spring 184 exerts aforce against the section 334 along a line that is perpendicular to thatline. As the movement of the print face 142 is very small, thisrelationship remains essentially constant.

The feed pawl 190 is pivotally mounted by a pin 337. A spring 196, theforce of which is adjusted by a set screw 196', bears against anextension 340 of the pawl 190. A set screw 198 is adapted to provide astop to limit the pivotal movement of the pawl 190 away from the coupledposition. As described above, when the electromagnet 158 is energized toenable lever 250 to be urged clockwise (FIG. 9) by the force of spring253, the shaft also rotates clockwise. With reference to FIG. 14, whenthe shaft 165 rotates clockwise, a roller 342 rotatably mounted by ashaft 343 secured to the extension 340 loses contact with elongated land344 of the shaft 165, thereby enabling the spring 196 to urge the pawlcounterclockwise to eflect uncoupling of the carriage 164 from the feedscrew 193 and return of the carriage 164 to the start-ofline positionunder the force of the carriage return spring 277. Both driving andguiding of the carriage 164 takes place at the bearing 308. The drivingforce is imparted directly to the bearing 308 by the pawl 190. Asdriving and guiding of the carriage 164 occur at the same place notwisting moment is imparted to the carriage 164. Yet, driving force iseither applied to or removed from the carriage 164 by pivoting the shaft165 into either one of two positions. A roller 342' is rotatably securedto the carriage frame 309 by a pivot screw 342". The roller 342' makesrolling contact with the shaft 165. Even though the shaft 165 is pivotedto move pawl 190 between coupled and uncoupled positions, there is notendency to pivot the carriage 164 about the feed screw 193 because theouter surface of the shaft 165 is circular and the shaft 165 rotatesabout its own axis. During travel of the carriage 164 away from thestart-of-line position the force which the land 344 of the shaft 165exerts on the roller 342 exerts a force on the pawl 190 driving the pawl190 into meshing engagement with the feed screw 193. This serves to keepthe carriage 164 from rocking when the print hammer 299 moves into andout of printing cooperation with platen elements 138. During carriagereturn, the feed screw 308 and the shaft 165 are the sole guides for thecarriage 164.

The feed screw 193 is driven one revolution each time the clutch 203 isengaged. The clutch 203 is engaged each time latch 227 (FIG. 11) istripped upon energization of coil 232 of electromagnet 229. Tripping ofthe latch 227 enables unitary lever 234 to be pivoted counterclockwise(FIG. 11) by the force of spring 236, enabling stop arm 240 to pivot outof abutment with tooth 241. When the clutch element 214 rotates, thetooth 241 and cam 239 on its outer surface rotate with it. Arm 238 rideson the outer surface of the element 214. When the cam 239 drives theentire lever 234 clockwise the latch 227 is relatched and the element114 stops rotating when the tooth 241 again engages the arm 240.

The printer 37 shown in FIGS. 1 and 7 through 19 is also useful in theembodiment of FIGS. 20 and 22 through 34 and in the embodiment of FIG.35. In FIG. 20, there is shown the platen 127 with its plurality ofplaten elements or edges I38 mechanically coupled as indicated at 400 toa clock wheel 401. Sensing members in the form of transducers 402 and403 are in electromagnetic sensing cooperation with two sets of clockelements formed by four slots 402' and forty slots 403', respectively.There are four locations where the slots 402' and the slots 403'coincide, as best shown in FIGS. 20 and 26. By way of example notlimitation, the mechanical coupling 400, which includes the pulley 200,the belt 201, the pulley 202, and gears 307 and 308, provides a driveratio that causes the clock wheel 401 to rotate six times faster thanthe platen 127; the platen 127 has twenty-four platen elements 138, andthus each one of the slots 402' corresponds to one of the platenelements 138.

Referring now more specifically to FIGS. 20 and 22 of the drawings,therein is illustrated a data-transmitting system which embodiesthe'present invention and in which the code converter or translatingfacilities are located at a receiving station. The system includes atransmitter 404 disposed at a location geographically remote from areceiving station and coupled thereto over a channel indicated generallyas 404. The transmitter 404 supplies message information over thechannel 404 using any suitable code, but in the illustrative exampleuses a five-bit or unit Baudot code in which mark and space conditionsare represented by signals of different frequencies. The receiverincludes a suitable coupling or interface unit 405 and an amplifier 406for supplying the received signals to a tone detector 407, the output ofwhich is supplied through an amplifier 408 to a filter capacitor 409 toprovide a generally steady state potential representing mark or spaceconditions. In the illustrated circuit, a more positive or high signalrepresents a mark signal, and a more negative or low signal represents aspace condition.

The incoming signals received from the transmitter 404 and provided atthe output of the amplifier 408 are stored in the receiver in theirBaudot coded form and are then translated to select a particular writeconductor selectively threaded through the cores of a core storage andtranslating matrix to cause the storage of each received character inthe core matrix in the coded form used by the printer. Following thestorage of the received character in the core storage matrix, the storedcharacter is read out of the matrix bit by bit to control the operationof the printer.

More specifically, the voltage level signals provided at the output ofthe amplifier 408 are forwarded through a pair of inverting amplifiersprovided by single-input NAND-gates 410 and 413 to one input of aNAND-gate 415 over a conductor 416 (FIGS. and 22). The other threeinputs to the gate 415 are connected to the 0 or inverted outputs ofthree flip-flops A, B, and C forming an input counter 500 (FIG. 22). Inthe normal state of the receiver, the inverted outputs A, B, and C(shown in the drawings as A, for example) are at the high levelpotential, and the output of the gate 413 is also at a high level sothat the output of the gate 415 is at a low level. The output of thegate 415 is forwarded through an inverting amplifier 417 to apply a morepositive potential to the emitter of a transistor in a time-basegenerator or free-running multivibrator 418 (FIGS. 22 and 28) so as tomaintain the generator"418 in an inoperative state. The time basegenerator 418 operates at the bit or unit rate of the received Baudotcode.

When the space signal at the beginning of a received character, forexample the character E is received, the conductor 416 drops to a lowlevel, the output of gate 415 rises to a higher level, and the gate 417provides a return for the emitter of the input transistor in thetime-base generator 418. Thus, the free-running multivibrator 418 isplaced in operation. One output of the time base generator 418 iscoupled to the clock input of the input flip-flop or stage A in thecounting circuit 500 so that the counting circuit 500 is advanced by thetime-based generator 418 in synchronism with the bits of the receivedcharacter code. The counting circuit 500 controls the selective readingof the bits of the received code into five flip-flops 502, the inputs ofwhich are coupled to the outputs of the inverters 410 and 413 over twoconductors 412 and 414, respectively.

Accordingly, when the first output pulse is delivered by the generator418, the flip-flop A is set to provide a more positive output signal A,while the flip-flops B and C provide the high inverted output signals Band C. None of the flip-flops 502 are enabled at this time inasmuch asthe first bit received from the signaling channel 404 is a space signalforming a start bit. When the generator 418 delivers a second pulse tothe counting circuit 500, the flip-flop A is reset, the flip-flop B isset, and the flip-flop C remains reset so that the output signal B andthe inverted output signal C are at a more positive potential. Thiscompletes the enabling of a gate 504 to supply a negative-going clock ortoggle signal to the flip-flop 502 in which is stored the firstintelligence bit of the received character. Assuming that the receivedcharacter is an E," the bit received from the channel 404 is a marksignal so that the output of the inverter 413 is more positive, and theoutput of the inverter 410 is at a low potential. These potentials areforwarded over the two conductors 412 and 414 to two inputs of the unit502 so that the first storage flip-flop 502 is set when clocked by thegate 504, and the first flip-flop 502 provides a high signal l and a lowlevel inverted signal l During the receipt of the next four operating orclock signals from the time base generator 418, the counting circuit 500is operated through four additional steps to provide in sequence the frJ ur output signal or voltage patterns: A, B, C; A, B, C; A, B, C; andA, B, C. In these four settings, the next four flip-flops 502 areenabled in sequence by the pattern of output potentials provided by thecounting circuit 500 either directly or through gates similar to thegate 504, as shown in FIG. 22 of the drawings. Since the Baudot code forthe character 13" includes spaces in the second through fifthintelligence bits, none of the remaining flip-flops 502 is set. Thus, atthe end of the receipt of these five intelligence bits in the receivedBaudot coded character E," the first flip-flop S02 is set, and theremaining four flip-flops 502 are in a reset condition.

The next received bit from the signaling channel 404 is a mark bitrepresenting the stop unit of the code. During the receipt of this code,the seventh operating pulse provided by the time base generator 418advances the counting circuit 500 to a setting in which all of theinverted outputs of the flip-flops A, B, and C are at a high level.Return of the counter 500 to this setting is used to terminate operationof the time base generator 418. More specifically, the time basegenerator 418 was placed in operation by the low level signal applied bythe conductor 416 to one input of the gate 415 when the space bitforming the start code was received. When the generator 418 advances thecounter 500 to its first setting, the flip-flop A is set so that theinverted output signal A from this flip-flop applied to one input of thegate 415 dropped to a low level and thus maintained through the inverter417 the enabling for the generator 418. At least one of the flip-flopsA, B, and C in the counting circuit 500 was maintained in a setcondition during subsequent settings of the counter 500 until theseventh pulse is received. At that time and as set forth above, all ofthe flip-flops AC are reset, and all of the inverted inputs A-C to thegate 415 are returned to a high level. The conductor 416 is also at ahigh level at this time because of the received mark bit forming thestop code, and the output of the gate 415 drops to a low level and isforwarded through the inverter 417 to inhibit further operation of thetime base generator 418. Thus, the generator is placed in operation onthe receipt of the start code and is rendered effective or inhibited onthe receipt of the stop code.

Thus, the receiver now has stored the received character E. in Baudotcode in the five flip-flops 502 associated with the input counter 500.The receiver, however, requires one additional item of informationbefore an accurate translation of the stored character into the printercode can take place. More specifically, it is necessary to store anindication of the lower case or letter shift on the one hand or an uppercase or figure shift on the other hand in order to adequately translatethe received code stored in the flip-flops 502. This function isperformed by a flip-flop 434 (FIG. 20), the inputs of which are providedwith the signal 3" or the inverted'signal 3 from the third flip-flop502. The clock input of the flip-flop 434 is connected to the output ofa gate 431, the inputs of which are connected to and enabled by thesetting of the first, second, fourth, and fifth flip-flops 502. Thesefour bits are common to both figure shift and letter shift, and thesetwo combinations differ from each other only in the presence or absenceof a mark bit in the third position of the Baudot code. Thus, when acomplete character code has been stored in the flip-flops 502representing either a letter shift or a figure shift, the gate 431 isfully enabled during the receipt of a fifth intelligence bit by aflip-flop 423 in the manner set forth in detail below to provide anegative-going clock signal to the input of a flip-flop 434. if a figureshift has been received, the inverted input signal 3" is high and theflip-flop 434 is reset. Alternatively, if a letter shift has beenreceived, the input signal 3" to the flipflop 434 is high, and thisflip-flop is set. Thus, the set condition of the flip-flop 434 indicatesreception in lower case, and the reset condition of the flip-flop 434indicates reception in upper case. The output signals derived from theflip-flop 434 are represented by the 0."

As indicated above, the character stored in Baudot form in theflip-flops 502 is decoded and stored in a core matrix 437 in thepositional code used to control the printer. The core matrix includes 35cores Cl-C35 arranged in five vertically extending columns eachcontaining seven cores corresponding to the 35 active positional codebits used by the printer. The Baudot coded character stored in the fiveflip-flops 502 is translated to and stored in the core matrix 437, inthe bits of the positional code required by the printer, by providing aseparate write conductor selectively linking those of the cores in thematrix 437 required by the positional code for the character and byenergizing the particular write conductor in accordance with atranslation of the code bits stored in the flip-flops 502.

As an example, FIG. 23 of the drawings illustrates a write conductor 438which links 19 of the 35 cores in the matrix 437 corresponding to thebits'of the positional code of the character E. When the conductor 438is energized, the linked cores or the cores through which the conductor438 is threaded are set to store the character E in the matrix 437 inthe form of the required bits of the positional code used by theprinter. These write conductors such as the write conductor 438 areselectively energized by translating the character stored in theflip-flops 502.

More specifically, the output signals 1, 2," and 3 from the threeflip-flops 502 are supplied to a translating network 435 of conventionalconstruction which translates the three input signals into a singleoutput marking condition applied to the gate electrode of one of eightsilicon-controlled rectifiers, one of which is identified as SCR-Zl-l.The cathodes of these SCRs are connected in common and over a conductor442 to the output of a monostable pulse generator 440. The anodes of thesilicon controlled rectifiers are connected to eight diode networks435-1 to 435-8. One end of each of the write conductors is connected toone of the diodes in the diode networks 435-1 to 435-8.

The other end of each of the write conductors is connected to thecathode of one of eight silicon-controlled rectifiers such as asilicon-controlled rectifier SCR-6V. The anodes of these rectifiers areconnected to a source of positive potential, and the gate electrodes ofthese rectifiers are connected to the output of a conventionaltranslating network 436. The translating network 436 is supplied withthe output signals 4" and 5" from the last two storage flip-flops 502,and the output signal (D from the flip-flop 434. The network 436translates the three input signals into one of eight output-markingconditions applied to the gates of the rectifiers such as the rectifierSCR- 6V. As illustrated in FIG. 23, the write conductor 438 for thecharacter E" is terminated at one end by connection to the cathode ofthe rectifier SCR-6V, and at the other end by connection through one ofthe diodes in the network 435-2 to the anode of the rectifier SCR-ZH.With a Baudot coded E stored in the flip-flops 502 and the flip-flop 434set for letter shift, a marking or enabling signal is applied to thegate electrodes of the two rectifiers SCR-6V and SCR-2H to condition theconductor 438 for energization.

The character stored in the flip-flops 502 is translated and stored inthe matrix 437 after the fifth bit of the received Baudot code has beenreceived and when one of the elements 138 on the platen 127 is in aproper position to begin recording. More specifically, when the fifthreceived intelligence bit of the code is stored in the fifth flip-flop502 under the control of the signals 8' and C, a gate 419 (FIGS. and 22)is partially enabled by these same signals, and the enabling iscompleted by a more positive signal received from the time basegenerator 418 from the collector of the input transistor (FIG. 28). Whenthe gate 419 is fully enabled, a more negative potential is applied to areset terminal of the flip-flop 423 over a conductor 424 so that the 0"terminal of this flip-flop rises to a more positive potential. This morepositive potential is applied to the set input of the flip-flop 423 andis also forwarded through the diode 431' to enable the extended input tothe gate 431. This low input is also applied over a conductor 426 (P16.20) to one input of a gate 425 to drive the output of this gate to amore positive potential which is forwarded over a conductor 430 to theclock or toggle input of the gate 423. The output of the gate 425 ismaintained at this high potential by an inverter 429, the output ofwhich is coupled to one input of the gate 425, and the input of which iscoupled to the output of a photocell amplifier 402". The input to theamplifier 402" is coupled to the transducer or sensor 402 so that theamplifier 402 normally provides a more positive output or high leveloutput except when one of the slots 402 on the clock wheel 401 is inreading or sensing position.

At the end of the pulse supplied by the time base generator 418, thegate 419 is no longer fully enabled, and its output rises to a morepositive potential to partially enable the gate 425 and to remove theresetting clamp from the flip-flop 423. When one of the vanes 138 of theplaten 127 next moves to a proper synchronized position for initiating arecording operation, the transducer 402 senses the presence of the slot402' and the amplifier 402" is effective through the inverter 429 tocomplete the enabling of the gate 425. Thus, a negative-going pulse isapplied to the clock terminal of the flip-flop 423, and this flip-flopis set so that its set output provides a more positive potential and alow level potential is derived from the reset output. This setting ofthe flip-flop 423 initiates the transfer of the character from theflip-flops 502 to the magnetic core matrix 437.

MOre specifically, when the flip-flop 423 was in its reset condition,the more positive potential derived from its reset output forwarded overa conductor 423" to the input of a gate 423 initiated the charging of acapacitor (FIG. 29) if a con ductor 441 connected to a resistive inputof the gate 423, is returned to a more negative or ground potential.When the flip-flop 423 is set and a more negative potential is derivedfrom the reset terminal of the flip-flop 423, the gate 423' triggers themonostable circuit 440 (FIG. 29) so that an output transistor is placedin a conductive condition to return an output conductor 440' to nearground potential. This enables the circuit including thesilicon-controlled rectifiers SCR-6V and SCR-ZH so that the conductor438 is energized to set the cores linked thereby, thus causing thestorage of the character 13" in the magnetic core matrix 437 in the bitsof the positional code. Further, when the output conductor 440' isreturned to a more negative potential, the winding 232 is energized torelease the one-revolution clutch 203 so that the carriage, and thepring hammer 299 which it carries, are advanced through one symbolspace. After the delay interval of the monostable circuit 440, theoutput conductor 440' is returned to a more positive potential toterminate the energization of the winding 232 and the write conductor438, Thus, the received character E" has now been stored in the matrix437 and the one-revolution clutch 203 has been released to initiate theprinting operation.

in certain instances, generally those when a control code is receivedfrom the line, it is desirable not to store the received control code inthe matrix 437 or to initiate movement of the carriage 164 containingthe print hammer 299. This function is performed by the gate 431 and apair of additional gates 432 and 439. As an example, a case shift codeis not to be stored in the matrix 437, and thus whenever the gate 431 isfully enabled, a more negative signal is applied to one input of thegate 439 which drives the output of this gate or the conductor 441 to amore positive potential. This prevents charging of the capacitor in theinput to the monostable 440 and prevents the setting of the monostablecircuit 440. Similarly, when a blank or line feed code is received, thegate 432 will be fully enabled ductive transistor 024 (FIG. 30) tomaintain the hammer in a retracted position. However, when a morenegative potential is applied to the circuit 455, the transistor 024 isplaced in a nonconductive condition, the energization of the winding 316is terminated, and the hammer 299 strikes against the adjacent recordingelement 138 of the platen 127 to produce a record in the area shown asL13 in FIG. 21. The circuit 454 is shown and described in detail in US.Pat. No. 3,386,378, and the transistor Q24 corresponds to the transistor24 in this patent.

The negative-going pulse on the conductor 452 which sets the flip-flop452 also applies a more negative input to the upper input of the gate449 so that its output rises to a more positive potential. Since themomentary negative-going pulse on the conductor 448' has now beendissipated, both inputs to the gate 449 are at a more positivepotential, and the output of this gate becomes more negative to hold theoutput of the gate 449' at a more positive potential. The output of thegate 449 also applies a more positive input to the reset input terminalof the flip-flop 451, and the input to the reset input of the flipfiop451 is now at a more positive potential. Thus, if a bit is not stored inthe next interrogated core in the matrix 437, the negative-going pulseapplied to the conductor 452 by the monostable circuit 452 will resultin resetting of the flip-flop 451. Alternatively, if a pulse is receivedfrom the sense winding 447 on interrogation of the next core, theflip-flop 451 will merely remain in its set condition even though thebistable circuit 450 will have been operated between its two alternatestates by the time the next clock pulse is received on the conductor 452The remaining nine pulses developed by the slots 403' on the clock ortiming wheel 401 advance the counter 506 through a cycle of operation,and as the counter 506 is advanced through this cycle of operation, theremaining horizontal read conductors including the conductor 2H areenergized in sequence to interrogate the remaining cores C2-C7 in thefirst column in sequence in the manner described above. This producesintermittent operation of the print hammer 299 under the control of thewinding or print coil 316 in dependence on the bit stored in the firstcolumn in the matrix 437.

As the counter 506 advances through the cycle of operation and returnsto its normal state, the translating or decoding network 446, in passingbeyond the position at which the uppermost of the horizontal readconductors is enabled, delivers an operating signal over a conductor446' to the clock terminal of the first flip-flop CE in the countingcircuit 508. This advances this counting circuit a single step to removethe enabling potential from the gate electrode of the rectifier 445-1connected to the first vertical read conductor 1V and to apply anenabling potential to the gate terminal of the rectifier terminating oneend of the second column or vertical read conductor 2V. Thus, during thenext cycle of operation of the counting circuit 506, the seven cores inthe second column are interrogated in sequence using coincident currenttechniques. In a similar manner, the counting circuits 506 and 508 andthe translating networks 446 and 445 interrogate the remaining cores inthe matrix 437 to control the application of signals over the sensewinding 447 to the amplifier 448 which in turn controls the setting ofthe flip-flop 451 and the energization of the winding 316 to effectrecording of the desired character.

A gate 514' (FIG. 22) is enabled by the flip-flops CF and CG and theoutput of the amplifier 403" at the conclusion of the scanning of thematrix 437 to reset the flip-flop 510 to a reset state in which a morenegative potential is provided at the set output of this flip-flop. Thisremoves the enabling potential from one input to the gate 512 and primesthe flipflop 451 to its reset state in which a more positive potentialis applied to the circuit 455. This aids in restoring the receivercircuit to a normal condition awaiting the receipt of the next Baudotcoded character in the flip-flops 502.

' In this manner, each character received from the channel 404' isstored in the flip-flops 502 in Baudot coded form and then stored intranslated form in bits of a positional code in the "core matrix 437.Following this storage, each of the bits stored in the matrix 437 isread out to control the actuation of the print hammer 299. All of theseoperations are synchronized with the rotation of the platen 127 throughthe clock wheel 401 and the related pickups or transducers 402 and 403.

With particular reference to FIG. 21, it is noted that the letter 12" isprinted at predetermined ones of the grid block locations L13 throughL59. Once the operation of the commutator 444 is initiated, thecommutator 444 is driven one step or count each time the transducer 403senses the slot 403', thereby advancing the commutator from Count '0 toCount 1 represented by grid block location L1 in FIG. 21 (even though nodot or mark can be printed until Count 12 is reached). When the nextslot 403 is sensed by the transducer 403, the commutator 444 is advancedfrom Count I to Count 2 represented by the grid block location L2. Whenthe transducer 403 senses the next slot 403', the commutator 444 isadvanced from Count 2 to Count 3 represented by grid blocklocation L3.The time between Count 0 and Count 12 provides more than adequate timefor the clutch 203 to be engaged, for the feed screw 193 to reachconstant rotational speed, and for storing the signal representative ofthe symbol in the memory device 437. It is apparent from FIG. 20 thatthe symbol signal is stored in the 5X7 array or matrix, and hence thesymbol is printed on the record medium in a 5X7 grid block arrange mentat predetermined locations between location L13 and location L59,inclusive. Printing can commence at location L13 when the commutator 444starts advancing from Count 12 to Count 13. As the print coil 316remains deenergized from Count 12 up to Count 19 the print hammer 299remains in printing cooperation with the platen element 138, therebycausing the vertical line portion of the symbol E to be scribed. Theprint coil 316 is energized as soon as printing has occurred at locationL19, so that no printing will occur at location L20. There is no core inthe memory device 437 which corresponds to location L20. The commutator444 continues to be advanced by each successive slot 403' from Count 19to Count 22. When Count 22 is reached the next successive platen element138 is in the proper position with respect to the print face 142. Thetime interval between Count 19 and Count 22 provides time for the nextsuccessive platen element 138 to rotate into proper position withrespect to the print face 142 of the print hammer 299. In like manner,all the dots or marks in the vertical column with grid block locationsL33 through L39 are printed when the print hammer 299 cooperates withthe next successive platen element 138, and so on. Progressive printingof the symbol E" is complete when a dot or mark is printed at locationL59.

In the embodiment of FIGS. 20 and 22 through 34 and also in theembodiment of FIG. 35, two sensing members, specifically transducers,402 and 403 are used in conjunction with the clockwheel 401. Thearrangement by which the clockwheel 401 and the sensing members 402 and403 are mounted in the printer 37 is illustrated in detail in FIGS. 25,26 and 27. Electric motor 199 is secured to a subframe 121' by fasteners470. The subframe 121' is secured to the printer frame 121. The subframe121 has an upstanding portion 472 which threadably receives a machinescrew 473. A mounting assembly 474 has a central bearing 475 received bymotor shaft 476. The mounting assembly 474 includes a pair of clamp arms477 and 478 which mount the sensing members 402 and 403. The clockwheelis secured to the shaft 476. The sensing member 402 is disposedoutwardly of and in alignment with the four slots 402', and the sensingmember 403 is disposed outwardly of and in alignment with the four slots402, and the sensing member 403 is disposed outwardly of and inalignment with the forty slots 403'. As best shown in FIG. 27, thesensing member 402 is clamped in position when machine screw 438 istightened. The gap between the sensing member 402 and the outer surfaceof the clockwheel 401 can be adjusted by loosening the machine screw488, making the adjustment, and thereafter tightening the machine screw488 to hold the sensing member 402 in its adjusted position. The sensingmember 403 is adjustably clamped by structure like that shown in FIG.27. The mounting structure 474 is always centered on the shaft 476.Thus, as the shaft 476 rotates, the sensing members 402 and 403 arealways in adjusted relationship with respect to the outer surface of theclockwheel 401. The slots 402' and 403' are made long enough so that inspite of any end play in the shaft 476 the sensing members 402 and 403are not affected by it. As best shown in FIG. 26, the sensing members402 and 403 are 180 apart.

in printing of a selected symbol on the record medium R, any dot or markwhich is to be printed in the first column, that is, at any one of thegrid block locations L13 through L19, is printed by the print face 142of the print hammer 299 cooperating with one of the platen edges; anydot or mark which is to be printed in the second column, that is, at anyone of the locations L23 through L29 is printed by the print face 142with the next successive platen edge 138; and so on. When a symbolsignal has been read into the memory device 437, the first slot 402'sensed by the sensing member 402 will start the commutator 444. Theremaining slots 402' have no effect on the commutator 444 which is nowadvanced under the control of slots 403' and sensing member 403. Theplaten element 138 which is presented in the printing zone when thecommutator 444 reaches Count 12, in cooperation with the print face 142,will effect printing at each location L13 through L19 where required asdictated by signal stored in the memory device 437; the next platenelement 138 on the outer surface on the platen 127 will effect printingat each location L23 through L29; and so on. Thus, once the symbol isready to be printed, any one or all of five successive platen elementsare used.

in order to insure that the printing cycle is always initiated such thatthe platen element which can print at the first seven vertical locationsL13 through L19 is in the proper position with respect to the print face142, it is desirable to provide for rotation of the sensing members 402and 403 as a unit with respect to the clockwheel 401. To this end, anarcuate slot 489 is provided for the mounting assembly 474. The machinescrew 473 passes through the center of the slot 489. When the screw 473is tightened, the mounting assembly 474 is clamped to the upstandingportion 472 of the subframe 121'. To adjust the sensing members 402 and403 with respect to the clockwheel 401, the screw 473 is loosened andthe mounting assembly 474 is rotated with respect and about the shaft476. The screw 473 is tightened when the adjustment has been made,thereby clamping the mounting assembly 474 in its adjusted position. Bymounting the mounting assembly 474 directly on the shaft 476, thesensing members 402 and 403 always remain in adjusted positions relativeto the clockwheel 401 in radial directions outwardly from the axis ofthe shaft 476.

In the embodiment of FIG. 35 there is illustrated an arrangement bywhich signals can be stored in the memory device, such as the memorydevice 437, directly from a keyboard generally indicated at 495. inparticular, the arrangement shown in FIG. 35 is used to store a symbolrepresentative signal and to initiate the printing cycle by initiatingoperation of commutator 444 and by initiating engagement of the clutch203. The keyboard 495 has a plurality of keys 496. When a selected key496 is depressed, it completes a circuit via respective switch 497through its respective winding 438 to sense amplifier 498. Each winding438 is roped through the memory device in an arrangement representativeof the selected symbol. The sense amplifier 448 thereupon sets thecontrol flip-flop 423. When a gate 499 is enabled by the next clockelement 402', the flip-flop 423 is reset and operates a one-shot 440a,corresponding to the one-shot 440, thereby energizing clutch coil 229 toeffect engagement of the clutch 203. Resetting of the flip-flop 423 alsoinitiates operation of the commutator 444 (FIG. via conductor 443.Depression of a carriage return key 496 causes closure of switch 497',thereby operating one-shot 440a to energize the coil 229 and causinginverting amplifier 460a, which corresponds to inverting amplifier 460,to turn on silicon-controlled rectifier 461, thereby energizing carriagereturn coil 158.

Other embodiments and modifications of this invention will suggestthemselves to those skilled in the art, and all such of these as comewithin the spirit of this invention are included within its scope asbest defined by the appended claims.

We claim:

1. For a printing system: a transmitter having symbol selecting meansfor effecting generation of electrical signals and having signal storagemeans, each electrical signal having a multiplicity of selectivelyspaced sequential pulse units representative of the selected symbol,means responsive to said electrical signals for printing the selectedsymbols on a record medium, each symbol being progressively printedduring a printing cycle, said printing means including recording meanshaving a continuously moving first recording member, means forcontinuously driving said recording means, a carriage mounted for travelwith respect to said first recording member, said carriage having asecond recording member responsive to readout of symbol pulse units fromsaid storage means and cooperable with said first recording member forprogressively printing the selected symbol on the record medium duringthe progressive printing cycle while said carriage is travelling,start-stop means for starting and stopping said carriage once for eachprinting cycle, means attached to said recording means and having firstand second sets of indicating means, said first set of indicating meansbeing representative of the position of said first recording member,first responsive means responsive to said first indicating means forsynchronizing the initiation of each printing cycle with the position ofsaid first recording member, and second responsive means responsive tosaid second indicating means for controlling actuation of said secondrecording member during the printing cycle.

2. For a printing system: means responsive to electrical signals forprinting symbols on a record medium, each electrical signal having amultiplicity of selectively spaced sequential symbol pulse unitsrepresentative of the selected symbol, each symbol being progressivelyprinted during a printing cycle, said printing means including recordingmeans having a continuously moving first recording member, means forcontinuously driving said recording means, a carriage mounted for travelwith respect to said recording means, said carriage having a secondrecording member responsive to said symbol pulse units and cooperablewith said first recording member for progressively printing the selectedsymbol on the record medium during the progressive printing cycle whilesaid carriage is traveling, start-stop means for starting and stoppingsaid carriage once for each printing cycle, means attached to saidrecording means and having first and second sets of indicating means,said first set of indicating means being representative of the positionof said first recording member, first responsive means responsive tosaid first indicating means for synchronizing the initiation of eachprinting cycle with the position of said first recording member, andsecond responsive means responsive to said second indicating means forcontrolling actuation of said second recording member during theprinting cycle.

3. For a printing system: a transmitter having symbol selecting meansfor effecting generation of electrical signals and having commutatormeans, each electrical signal having a multiplicity of selectivelyspaced sequential pulse units representative of the selected symbol, aprinter responsive to said electrical signals for printing the selectedsymbol on a record medium, said selected symbol being progressivelyprinted during a printing cycle, said printer having at least one movingplaten element, printing means cooperable with said platen element, acarriage mounting said printing means for relative movement with respectto said platen element, startstop means for causing said carriage tostart, travel and stop once for each symbol recordation, meansassociated with said platen element and having first and second sets ofindicating means, said first set of indicating means beingrepresentative of the position of said platen element, commutator means,first responsive means responsive to said first indicating means when aselected symbol is to be printed for initiating operation of saidcommutator means, and second responsive means responsive to said secondindicating means for thereafter driving said commutator means to effectprogressive printing of the selected symbol on the record medium as saidcarriage travels.

4. For a printing system: a printer for progressively printing symbolsin successive symbol rectangular spaces on a record medium, said printerhaving at least one moving first recording member, a second recordingmember cooperable with said first recording member, a carriage mountingsaid second recording member for relative movement with respect to saidfirst recording member, start-stop means for causing said carriage tostart, travel and stop once for each symbol recordation, meansassociated with said first recording member and having first and secondsets of indicating means, said first set of indicating means beingrepresentative of the position of said first recording member,commutator means, first responsive means responsive to said firstindicating means when a selected symbol is to be printed for initiatingoperation of said commutator means, and second responsive meansresponsive to said second indicating means for thereafter driving saidcommutator means to effect progressive printing of the selected symbolon the record medium as said carriage travels.

5. For a printing system: means responsive to electrical signals forprinting symbols on a record medium, each electrical signal having amultiplicity of selectively spaced sequential symbol pulse unitsrepresentative of the selected symbol, each symbol being progressivelyprinted during a printing cycle, signal storage means, said printingmeans including recording means having a continuously moving firstrecording member, means for continuously driving said recording means, acarriage mounted for travel with respect to said recording means, saidcarriage having a second recording member responsive to readout ofsymbol pulse units from said signal storage means and cooperable withsaid first recording member for progressively printing the selectedsymbol on the record medium during the progressive printing cycle whilesaid carriage is traveling, means attached to said recording means andhaving first and second sets of indicating means, said first set ofindicating means being representative of the position of said firstrecording member, first responsive means responsive to said firstindicating means for synchronizing the initiation of each printing cyclewith the position of said first recording member, and second responsivemeans responsive to said second indicating means for controlling rate ofreadout from said storage means during the printing cycle.

6. For a printing system: recording means having at least onecontinuously moving line-shaped first recording member, means forcontinuously driving said recording means, a carriage mounted for travelwith respect to said first recording member, said carriage having aline-shaped recording member cooperable with said first recording memberfor progressively printing the selected symbol on the record mediumduring the progressive printing cycle while said carriage is traveling,start-stop means for starting and stopping travel of said carriage oncefor each printing cycle, means attached to said recording means hadhaving first and second sets of indicating means, said first set ofindicating means being representative of the position of said firstrecording member, first responsive means responsive to said firstindicating means for synchronizing the initiation of each printing cyclewith the position of said first recording member, and second responsivemeans responsive to said second indicating means for controllingactuation of said second recording member during the printing cycle.

7. For a printing system: a printer for progressively printing symbolsat predetermined grid block locations in successive symbol rectangularspaces on a record medium, said printer having at least one movingplaten element, print hammer means actuatable into and out of printingcooperation with said platen element, a carriage mounting said printhammer means for relative movement with respect to said platen element,means for sensing the position of said platen element,

and means responsive to said sensing means for controlling initiation ofthe printing cycle and for thereafter controlling said print hammermeans to print at each predetermined grid block location until theentire symbol has been printed.

8. A recording unit as defined in claim 7, wherein said sensing meansincludes a first sensing device which senses when the moving platenelement is in a predetermined initial position and a second sensingdevice which senses when the moving platen element is in other positionscorresponding to rows in the grid block arrangement, means for detectingwhen a symbol signal has been received, said printing cycle beinginitiated when said detecting means has detected a symbol signal andsaid first sensing device has sensed the initial position of said platenelement, and wherein said print hammer enabling means is responsive tosaid second sensing device.

9. A recording unit as defined in claim 7, wherein said controllingmeans includes a commutator, means connecting said sensing means andsaid commutator for initiating operation of said commutator and foradvancing said commutator as said platen element moves.

10. For a printing system: a recording unit, capable of receivingsignals, for visually recording a selected symbol in a symbolrectangular space on a record medium, means for translating each of saidsignals into a corresponding electrical symbol signal having amultiplicity of intrasignal pulse units each of which corresponds to aspecific iocation in the symbol rectangular space, said recording meansincluding means for progressively printing the selected symbol, saidprinting means including platen means which moves during each symbolrecordation and print hammer means cooperable with said platen meanswhile said platen means moves, and means for continuously sensing theposition of said platen means, said translating means including meansresponsive to said sensing means for actuating said print hammer meansin accordance with the intrasignal pulse units of the selected signal.

11. The invention as defined in claim 10, said translating meansincluding signal storage means and a commutator for effecting readoutfrom said signal storage means, said sensing means being operative toadvance said commutator.

12. The invention as defined in claim 10, including a carriage mountingsaid printing means for travel with respect to said platen means, meansfor driving said platen means continuously and for starting, travel andstopping of said carriage once for each symbol recordation.

13. The invention as defined in claim 10, wherein said platen meansmoves continuously.

14. The invention as defined in claim 10, said translating meansincluding signal storage means and means responsive to said sensingmeans for reading said signal out of said storage means in the form ofsymbol pulse units representative of the symbol to be printed, saidsymbol pulse units being effective to actuate said print hammer means insynchronism with said platen means to print at grid block locations forthe selected symbol.

15. The invention as defined in claim [0, including a carriage formounting said printing means for travel with respect to said platenmeans, means for driving said platen continuously and for effectingstarting, travel and stopping of said carriage once for each symbolrecordation, said translating means including signal storage means andmeans responsive to said sensing means for reading said signal out ofsaid storage means in the form of symbol pulse units representative ofthe symbol to be printed, said symbol pulse units being effective toactuate said print hammer means in synchronism with said platen means toprint at grid block locations for the selected symbol.

16. The invention as defined in claim 10, said translating meansincluding means responsive to said sensing means for effectinginitiation of the printing of each successive symbol.

17. For printing system: means for printing successive symbols in a dotmatrix arrangement on a record medium, said printing means includingcontinuously moving platen means and a printing means cooperable withsaid platen means and mounted for travel relative to said platen means,means for storing symbol signals, means for continuously sensing theposition of said platen means, and means responsive to said sensingmeans for controlling the rate of readout of each symbol signal fromsaid storing means during each printing cycle.

18. The printing system as set forth in claim 17 wherein said responsivemeans initiates the readout of a signal from said signal storing means.

19. For use with a communication system: means for receiving codedsignals, means for translating each received signal into an electricalsymbol signal comprising a series of intrasignal pulse unitsrepresentative of the received signal, printing means including movingplaten means and cooperable movable print hammer means and means formoving said platen means, said print hammer means being responsive tosaid intrasignal pulse units and cooperable with said moving platenmeans for progressively printing a symbol representative of the receivedsignal on a record medium, said translating means including firstsensing means for sensing the position of said platen means, meansresponsive to said sensing means for synchronizing the actuation of saidprint hammer means with the position of said moving platen means, amagnetic core array having cores arranged in a two-dimensional array ofrows and columns, means for setting predetermined ones of said cores,means for attempting to reset all said cores in succession, and secondsensing means for detecting the resetting of said predetermined ones ofsaid cores.

20. For use with a communication system: means for receiving codedsignals, means for translating each received signal into an electricalsymbol signal comprising a series of intrasignal pulse unitsrepresentative of the received signal, printing means including movingplaten means and cooperable movable print hammer means and means formoving said platen means, said print hammer means being responsive tosaid intrasignal pulse units and cooperable with said moving platenmeans for progressively printing a symbol representative of the receivedsignal on a record medium, said translating means including means forsensing the position of said platen means and means responsive to saidsensing means for synchronizing the actuation of said print hammer meanswith the position of said moving platen means, said receiving meansincluding means for receiving Baudot Code in serial form and aserial-to-parallel converter operatively connected to said translatingmeans.

21. For use with a communication system: means for receiving codedsignals, means for translating each received signal into an electricalsymbol signal comprising a series of intrasignal pulse unitsrepresentative of the received signal, printing means including movingplaten means and cooperable movable print hammer means and means formoving said platen means, said print hammer means being responsive tosaid intrasignal pulse units and cooperable with said moving platenmeans for progressively printing a symbol representative of the receivedsignal on a record medium, said translating means including means forsensing the position of said platen means, means responsive to saidsensing means for synchronizing the actuation of said print hammer meanswith the position of said moving platen means, a commutator and atwo-dimensional magnetic core array, said sensing means effectsadvancement of said commutator and said commutator effects reading outof a stored symbol signal from said core array.

22. For use with a communication system: means for receiving codedsignals, means for translating each received signal into an electricalsymbol signal comprising a series of intrasignal pulse unitsrepresentative of the received signal, printing means including movingplaten means and cooperable movable print hammer means and means formoving said platen means, said print hammer means being responsive tosaid intrasignal pulse units and cooperable with said moving platenmeans for progressively printing a symbol representative of the receivedsignal on a record medium, said translating means including means forsensing the position of said platen means, means responsive to saidsensing means for synchronizing the actuation of said pnnt hammer meanswith the position of said moving platen means, an array of bistableelectronic components, means for setting predetermined ones of saidcomponents in accordance with the symbol represented by the receivedsignal, and means for reading out the condition of the cores of saidarray.

1. For a printing system: a transmitter having symbol selecting meansfor effecting generation of electrical signals and having signal storagemeans, each electrical signal having a multiplicity of selectivelyspaced sequential pulse units representative of the selected symbol,means responsive to said electrical signals for printing the selectedsymbols on a record medium, each symbol being progressively printedduring a printing cycle, said printing means including recording meanshaving a continuously moving first recording member, means forcontinuously driving said recording means, a carriage mounted for travelwith respect to said first recording member, said carriage having asecond recording member responsive to readout of symbol pulse units fromsaid storage means and cooperable with said first recording member forprogressively printing the selected symbol on the record medium duringthe progressive printing cycle while said carriage is travelling,start-stop means for starting and stopping said carriage once for eachprinting cycle, means attached to said recording means and having firstand second sets of indicating means, said first set of indicating meansbeing representative of the position of said first recording member,first responsive means responsive to said first indicating means forsynchronizing the initiation of each printing cycle with the position ofsaid first recording member, and second responsive means responsive tosaid second indicating means for controlling actuation of said secondrecording member during the printing cycle.
 2. For a printing system:means responsive to electrical signals for printing symbols on a recordmedium, each electrical signal having a multiplicity of selectivelyspaced sequential symbol pulse units representative of the selectedsymbol, each symbol being progressively printed during a printing cycle,said printing means including recording means having a continuouslymoving first recording member, means for continuously driving saidrecording means, a carriage mounted for travel with respect to saidrecording means, said carriage having a second recording memberresponsive to said symbol pulse units and cooperable with said firstrecording member for progressively printing the selected symbol on therecord medium during the progressive printing cycle while said carriageis traveling, start-stop means for starting and stopping said carriageonce for each printing cycle, means attached to said recording means andhaving first and second sets of indicating means, said first set ofindicating means being representative of the position of said firstrecording member, first responsive means responsive to said firstindicating means for synchronizing the initiation of each printing cyclewith the position of said first recording member, and second responsivemeans responsive to said second indicating means for controllingactuation of said second recording member during the printing cycle. 3.For a printing system: a transmitter having symbol selecting means foreffecting generation of electrical signals and having commutator means,each electrical signal having a multiplicity of selectively spacedsequential pulse units representative of the selected symbol, a printerresponsive to said electrical signals for printing the selected symbolon a record medium, said selected symbol being progressively printedduring a printing cycle, said printer having at least one moving platenelement, printing means cooperable with said platen element, a carriagemounting said printing means for relative movement with respect to saidplaten element, start-stop means for causing said carriage to start,travel and stop once for each symbol recordation, means associated withsaid platen element and having first and second sets of indicatingmeans, said first set of indicating means being representative of theposition of said platen element, commutator means, first responsivemeans responsive to said first indicating means when a selected symbolis to be printed for initiating operation of said commutator means, andsecond responsive means responsive to said second indicating means forthereafter driving said commutator means to effect progressive printingof the selected symbol on the record medium as said carriage travels. 4.For a printing system: a printer for progressively printing symbols insuccessive symbol rectangular spaces on a record medium, said printerhaving at least one moving first recording member, a second recordingmember cooperable with said first recording member, a carriage mountingsaid second recording member for relative movement with respect to saidfirst recording member, start-stop means for causing said carriage tostart, travel and stop once for each symbol recordation, meansassociated with said first recording member and having first and secondsets of indicating means, said first set of indicating means beingrepresentative of the position of said first recording member,commutator means, first responsive means responsive to said firstindicating means when a selected symbol is to be printed for initiatingoperation of said commutator means, and second responsive meansresponsive to said second indicating means for thereafter driving saidcommutator means to effect progressive printing of the selected symbolon the record medium as said carriage travels.
 5. For a printing system:means responsive to electrical signals for printing symbols on a recordmedium, each electrical signal having a multiplicity of selectivelyspaced sequential symbol pulse units representative of the selectedsymbol, each symbol being progressively printed during a printing cycle,signal storage means, said printing means including recording meanshaving a continuously moving first recording member, means forcontinuously driving said recording means, a carriage mounted for travelwith respect to said recording means, said carriage having a secondrecording member responsive to readout of symbol pulse units from saidsignal storage means and cooperable with said first recording member forprogressively printing the selected symbol on the record medium duringthe progressive printing cycle while said carriage is traveling, meansattached to said recording means and having first and second sets ofindicating means, said first set of indicating means beingrepresentative of the position of said first recording member, firstresponsive means responsive to said first indicating means forsynchronizing the initiation of each printing cycle with the position ofsaid first recording member, and second responsive means responsive tosaid second indicating means for controlling rate of readout from saidstorage means during the printing cycle.
 6. For a printing system:recording means having at least one continuously moving line-shapedfirst recording member, means for continuously driving said recordingmeans, a carriage mounted for travel with respect to said firstrecording member, said carriage having a line-shaped recording membercooperable with said first recording member for progressively printingthe selected symbol on the record medium during the progressive printingcycle while said carriage is traveling, start-stop means for startingand stopping travel of said carriage once for each printing cycle, meansattached to said recording means had having first and second sets ofindicating means, said first set of indicating means beingrepresentative of the position of said first recording member, firstresponsive means responsive to said first indicating means forsynchronizing the initiation of each printing cycle with the position ofsaid first recording member, and second responsive means responsive tosaid second indicating means for controlling actuation of said secondrecording member during the printing cycle.
 7. For a printing system: aprinter for progressively printing symbols at predetermined grid blocklocations in successive symbol rectangular spaces on a record medium,said printer having at least one moving platen element, print hammermeans actuatable into and out of printing cooperation with said platenelement, a carriage mounting said print hammer means for relativemovement with respect to said platen element, means fOr sensing theposition of said platen element, and means responsive to said sensingmeans for controlling initiation of the printing cycle and forthereafter controlling said print hammer means to print at eachpredetermined grid block location until the entire symbol has beenprinted.
 8. A recording unit as defined in claim 7, wherein said sensingmeans includes a first sensing device which senses when the movingplaten element is in a predetermined initial position and a secondsensing device which senses when the moving platen element is in otherpositions corresponding to rows in the grid block arrangement, means fordetecting when a symbol signal has been received, said printing cyclebeing initiated when said detecting means has detected a symbol signaland said first sensing device has sensed the initial position of saidplaten element, and wherein said print hammer enabling means isresponsive to said second sensing device.
 9. A recording unit as definedin claim 7, wherein said controlling means includes a commutator, meansconnecting said sensing means and said commutator for initiatingoperation of said commutator and for advancing said commutator as saidplaten element moves.
 10. For a printing system: a recording unit,capable of receiving signals, for visually recording a selected symbolin a symbol rectangular space on a record medium, means for translatingeach of said signals into a corresponding electrical symbol signalhaving a multiplicity of intrasignal pulse units each of whichcorresponds to a specific location in the symbol rectangular space, saidrecording means including means for progressively printing the selectedsymbol, said printing means including platen means which moves duringeach symbol recordation and print hammer means cooperable with saidplaten means while said platen means moves, and means for continuouslysensing the position of said platen means, said translating meansincluding means responsive to said sensing means for actuating saidprint hammer means in accordance with the intrasignal pulse units of theselected signal.
 11. The invention as defined in claim 10, saidtranslating means including signal storage means and a commutator foreffecting readout from said signal storage means, said sensing meansbeing operative to advance said commutator.
 12. The invention as definedin claim 10, including a carriage mounting said printing means fortravel with respect to said platen means, means for driving said platenmeans continuously and for starting, travel and stopping of saidcarriage once for each symbol recordation.
 13. The invention as definedin claim 10, wherein said platen means moves continuously.
 14. Theinvention as defined in claim 10, said translating means includingsignal storage means and means responsive to said sensing means forreading said signal out of said storage means in the form of symbolpulse units representative of the symbol to be printed, said symbolpulse units being effective to actuate said print hammer means insynchronism with said platen means to print at grid block locations forthe selected symbol.
 15. The invention as defined in claim 10, includinga carriage for mounting said printing means for travel with respect tosaid platen means, means for driving said platen continuously and foreffecting starting, travel and stopping of said carriage once for eachsymbol recordation, said translating means including signal storagemeans and means responsive to said sensing means for reading said signalout of said storage means in the form of symbol pulse unitsrepresentative of the symbol to be printed, said symbol pulse unitsbeing effective to actuate said print hammer means in synchronism withsaid platen means to print at grid block locations for the selectedsymbol.
 16. The invention as defined in claim 10, said translating meansincluding means responsive to said sensing means for effectinginitiation of the printing of each successive symbol.
 17. For printingsystEm: means for printing successive symbols in a dot matrixarrangement on a record medium, said printing means includingcontinuously moving platen means and a printing means cooperable withsaid platen means and mounted for travel relative to said platen means,means for storing symbol signals, means for continuously sensing theposition of said platen means, and means responsive to said sensingmeans for controlling the rate of readout of each symbol signal fromsaid storing means during each printing cycle.
 18. The printing systemas set forth in claim 17 wherein said responsive means initiates thereadout of a signal from said signal storing means.
 19. For use with acommunication system: means for receiving coded signals, means fortranslating each received signal into an electrical symbol signalcomprising a series of intrasignal pulse units representative of thereceived signal, printing means including moving platen means andcooperable movable print hammer means and means for moving said platenmeans, said print hammer means being responsive to said intrasignalpulse units and cooperable with said moving platen means forprogressively printing a symbol representative of the received signal ona record medium, said translating means including first sensing meansfor sensing the position of said platen means, means responsive to saidsensing means for synchronizing the actuation of said print hammer meanswith the position of said moving platen means, a magnetic core arrayhaving cores arranged in a two-dimensional array of rows and columns,means for setting predetermined ones of said cores, means for attemptingto reset all said cores in succession, and second sensing means fordetecting the resetting of said predetermined ones of said cores. 20.For use with a communication system: means for receiving coded signals,means for translating each received signal into an electrical symbolsignal comprising a series of intrasignal pulse units representative ofthe received signal, printing means including moving platen means andcooperable movable print hammer means and means for moving said platenmeans, said print hammer means being responsive to said intrasignalpulse units and cooperable with said moving platen means forprogressively printing a symbol representative of the received signal ona record medium, said translating means including means for sensing theposition of said platen means and means responsive to said sensing meansfor synchronizing the actuation of said print hammer means with theposition of said moving platen means, said receiving means includingmeans for receiving Baudot Code in serial form and a serial-to-parallelconverter operatively connected to said translating means.
 21. For usewith a communication system: means for receiving coded signals, meansfor translating each received signal into an electrical symbol signalcomprising a series of intrasignal pulse units representative of thereceived signal, printing means including moving platen means andcooperable movable print hammer means and means for moving said platenmeans, said print hammer means being responsive to said intrasignalpulse units and cooperable with said moving platen means forprogressively printing a symbol representative of the received signal ona record medium, said translating means including means for sensing theposition of said platen means, means responsive to said sensing meansfor synchronizing the actuation of said print hammer means with theposition of said moving platen means, a commutator and a two-dimensionalmagnetic core array, said sensing means effects advancement of saidcommutator and said commutator effects reading out of a stored symbolsignal from said core array.
 22. For use with a communication system:means for receiving coded signals, means for translating each receivedsignal into an electrical symbol signal comprising a series ofintrasignal pulse units representative of the received signal, printingmeans including movIng platen means and cooperable movable print hammermeans and means for moving said platen means, said print hammer meansbeing responsive to said intrasignal pulse units and cooperable withsaid moving platen means for progressively printing a symbolrepresentative of the received signal on a record medium, saidtranslating means including means for sensing the position of saidplaten means, means responsive to said sensing means for synchronizingthe actuation of said print hammer means with the position of saidmoving platen means, an array of bistable electronic components, meansfor setting predetermined ones of said components in accordance with thesymbol represented by the received signal, and means for reading out thecondition of the cores of said array.